Single‐Atom Cadmium‐N<sub>4</sub> Sites for Rechargeable Li–CO<sub>2</sub> Batteries with High Capacity and Ultra‐Long Lifetime
Kaige Zhu, Xin Li, Junyoung Choi, Changhyeok Choi, Song Hong, Xinyi Tan, Tai‐Sing Wu, Y. L. Soo, Leiduan Hao, Alex W. Robertson, Yousung Jung, Zhenyu Sun
Abstract
Abstract The rechargeable Li–CO 2 battery shows great potential in civil, military, and aerospace fields due to its high theoretical energy density and CO 2 capture capability. To facilitate the practical application of Li–CO 2 battery, the design of efficient, low‐cost, and robust non‐noble metal cathodes to boost CO 2 reduction/evolution kinetics is highly desirable yet remains a challenge. Herein, single‐atom cadmium is reported with a Cd‐N 4 coordination structure enable rapid kinetics of both the discharge and recharge process when employed as a cathode catalyst, and thus facilitates exceptional rate performance in a Li–CO 2 battery, even up to 10 A g −1 , and remains stable at a high current density (100 A g −1 ). An unprecedented discharge capacity of 160045 mAh g −1 is attained at 500 mA g −1 . Excellent cycling stability is maintained for 1685 and 669 cycles at 1 A g −1 and capacities of 0.5 and 1 Ah g −1 , respectively. Density functional theory calculations reveal low energy barriers for both Li 2 CO 3 formation and decomposition reactions during the respective discharge and recharge process, evidencing the high catalytic activity of single Cd sites. This study provides a simple and effective avenue for developing highly active and stable single‐atom non‐precious metal cathode catalysts for advanced Li–CO 2 batteries.